While Panic Control Treatment (PCT) has been found to be widely effective in the treatment of panic disorder in adults, no large-scale controlled treatment studies have evaluated the use of similar cognitive-behavioral approaches in the treatment of adolescents with panic disorder. Given that late adolescence has been suggested as the initial peak age for onset of panic disorder, the purpose of this project is to establish an empirically validated intervention aimed at treating panic disorder at its earliest stages. Specifically, the aims of this project are: to evaluate the effectiveness of a developmental adaptation of PCT for the treatment of panic disorder in adolescents; to determine the long-term impact of such treatment through follow-up assessment; and to assess the impact of treatment on the quality of life of adolescents beyond the specific symptoms of panic disorder. A total of 52 adolescents (aged 12 to 17) with a diagnosis of panic disorder, assessed via the Anxiety Disorders Interview Schedule, will be randomly assigned to either an immediate PCT treatment condition or to a self-monitoring waitlist in which participants will wait approximately 12 weeks prior to receiving PCT. All participants will undergo a pretreatment and a posttreatment/waitlist assessment, as well as three follow-up assessments, conducted 3-, 6-, and 12 months following completion of treatment. Assessments will consist of diagnostic interviews with adolescents and their parent(s), a behavioral and physiological assessment of response to symptom induction tasks designed to elicit sensations similar to naturally occurring panic, and self-report measures of anxiety, anxiety sensitivity, depression, and fear. Participants will also be asked to self-monitor their panic attacks as well as daily anxiety and depression. It is hypothesized that adolescents receiving PCT will evidence greater improvement than those in the waitlist group, and will continue to show improvement at follow-up, on panic-specific variables (e.g., frequency of panic attacks), psychopathology variables (e.g., anxiety sensitivity score), behavioral and physiological variables (e.g., average change in heart rate from baseline to the symptom induction tasks), and clinical severity ratings of panic disorder.